The invention relates to a side-curtain airbag for a curtain airbag module along with a corresponding curtain airbag module and a method of manufacturing a side-curtain airbag.
Side-curtain airbag modules in motor vehicles extend from a roof beam of the vehicle along the vehicle side. A side-curtain airbag generally extends from an A-pillar of a motor vehicle to a C-pillar of the vehicle along the side of the vehicle originating from the lateral roof beam of the vehicle. The inflated side-curtain airbag provides lateral protection for the head and upper body of the vehicle occupant. The side-curtain airbag in this case extends essentially parallel to the side window or the inner side of the vehicle between the head of the vehicle occupant and the vehicle side window. Since the side-curtain airbag extends along the entire length of the vehicle, it protects the occupants of the front seats as well as the occupants of the rear seats. In the region between front and rear seats, that is to say in the region of B-pillar of the vehicle, no protection is required. In this region of the side-curtain airbag is generally separated from inflation chambers by tucks, to keep the inflation chamber volume as small as possible. In this way, dead spaces are created, which during the inflation of the side-curtain airbag are not inflated with gas. The side-curtain airbag is generally manufactured from a coated fabric that is relatively costly. In addition, due to its large length, the side-curtain airbag requires a large amount of fabric, which adds to the cost of such side-curtain airbags.
The side-curtain airbag according to the invention has the advantage that, between the two inflation chambers at the most one layer of the fabric is located, from which the inflation chambers also are formed. Both inflation chambers, the first one of which is generally located in the region of a front seat of the vehicle and the second in the region of a rear seat of a vehicle, are thus not two continuous fabric pieces. The two inflation chambers are separate, whereby at the most one fabric layer of the fabric creating the inflation chambers is a continuous width of fabric extending over the entire length of the vehicle. In this way part of the costly fabric material, which creates the inflation chambers, can be economized on in comparison with former embodiments, in which regions between two fabric layers were separated from the inflation chambers by tucks. Because the inflation chambers are for the regions of the side-curtain airbag that protect a vehicle occupant, the required gas volume can be reduced. A reduced gas volume enables the use of smaller gas generators, which results in a further reduction in cost. In addition, a reduced gas or air volume results in a more rapid inflation of the side-curtain airbag, whereby the side-curtain airbag more rapidly assumes the desired position for the protection of the vehicle occupants. A smaller fabric surface also ensures lower friction during the unfolding process, thus also contributing to a more rapid unfolding process.
The curtain airbag module according to the invention comprises a side-curtain airbag with the above described characteristics. In this way it is possible to manufacture a particularly cost-effective side-curtain airbag module.